Teen Fatally Stabs Mother's Boyfriend After Man Assaults Boy's Mom: Fairfax County Police

HYBLA VALLEY, VA — A teen who police say stabbed his mother's boyfriend to stop an assault in Hybla Valley Sunday night has not been charged.

Before 10 p.m., police responded to an apartment in the 7900 block of Janna Lee Avenue after a caller said his mother was being assaulted by her boyfriend. Police say the caller was a teen who stabbed the mother's boyfriend.

Detectives' preliminary investigations determined the boyfriend was visiting when a verbal argument turned into an assault. The teen told police he stabbed the boyfriend to stop the assault.

Three other children in the apartment were not injured. The mother was treated for non-life-threatening injuries.

The man, Marcus Roberson, 32, of DC, was taken to the hospital and pronounced dead. An autopsy will be conducted to confirm the cause and manner of death.

While police have not charged the teen, detectives are continuing the investigation into whether the incident was a "justifiable homicide." Police will consult with the Commonwealth's Attorney's office to determine if charges will be placed.

Anyone with information about the incident can contact the Major Crimes Bureau at 703-246-7800 or submit a tip through Crime Solvers.